Sam-A Gaiyanghadao

Sam-A looks to win a second title as he will face Rocky Ogden for the inaugural ONE Muay Thai Strawweight World Championship at ONE Championship: King of the Jungle on February 28, 2020. After dominating the entire fight, Sam-A would go on to win by unanimous decision and become the first ONE Muay Thai Strawweight World Champion, becoming ONE Championship's second two-sport world champion in the process.

In his first title defense on May 4, 2019, he lost the title in upset fashion to England's Jonathan Haggerty by unanimous decision at ONE Championship: For Honor.

Following his title loss, Sam-A Gaiyanghadao moved down to strawweight and eventually made his return to ONE Championship on October 13, 2019 at Tokyo. He faced Daren Rolland in Part 1 of ONE Championship: Century, where he knocked out the Frenchman in the second round.

Sam-A Gaiyanghadao is scheduled to face Wang Junguang for the inaugural ONE Kickboxing Strawweight World Championship at ONE Championship: Mark Of Greatness on December 6, 2019. Sam-A defeated Wang Junguang by unanimous decision to become the first ONE Kickboxing Strawweight World Champion, as well as the second two-sport World Champion in ONE Championship.

On January 26, 2018, he faced Joseph Lasiri at ONE Championship: Global Superheroes in the promotion's first-ever Muay Thai contest, defeating the Italian via second-round TKO.

He followed that up with a KO victory over Sergio Wielzen on May 18, 2018 to claim ONE's inaugural ONE Super Series Muay Thai Flyweight World Championship at ONE Championship: Unstoppable Dreams.

On October 21, 2014, Sam-A defeated Andrew Doyle by fourth-round KO to win the WBC World 60 kg Title

Sam-A rematched Pokaew Fonjaenchonburi on February 7, 2013 and the pair fought to a draw.

He beat Yokwitaya Petsimean on points at Lumpinee Stadium on May 10, 2013.

He TKO'd Phet Utong Or. Kwanmuang in round two at Lumpinee Stadium on June 7, 2013.

Sam-a beat Superlek Wor Sangrapai on points to win the vacant Thailand super bantamweight title at Lumpinee Stadium on July 12, 2013.

On July 12, 2012, Sam-A had his first career professional boxing match. He fought Christian Abila and won by 4th-round TKO.

He was scheduled to rematch Penake Sitnumnoi on October 4, 2012 at Lumpinee but the fight was postponed when Penake suffered a shoulder injury.

He beat Petpanomrung Wor Sungprapai by decision at Lumpinee Stadium on November 2, 2012.

Sam-A is known for competing in the first Muay Thai match in ONE Championship. He is a former ONE Muay Thai Flyweight World Champion (being the first to hold the title), in addition to being a former four-division Thailand Champion and two-division Lumpinee Stadium Champion. His other Muay Thai accolades include being named Lumpinee Fighter of the Year and Sport Writers Friends Fighter of the Year, winning both awards in 2011. He is regarded as one of the best Muay Thai fighters in the world, and known for his strong defense and counter offense.

In 2011, he came back down to his natural weight and surpassed his 2008 year by going 8-0-1 and winning the Lumpinee Fighter of the Year award. His fight with reigning Fighter of the Year Kongsak Sitboonmee was amongst the biggest and most anticipated of the year. The fight was very close at the end and was ruled a draw. Soon after Sam-A's promoter told him he would buy him a new Toyota pickup truck if he won five straight fights. Sure enough he did, and Sam-A was awarded with a new Toyota pickup valued at over $50,000 after a dominant decision win over Tingtong Chor. Koyahu-Isuzu. In 2011, he changed his name from Sam-A Thor. Ratonakiat to Sam-A Gaiyanghadaogym. Despite having "gym" in the name, it is nothing more than a sponsor, with "Gaiyanghadao" literally meaning "5-star grilled chicken". For his first fight of 2012, he defeated Rungruanglek Lukprapbart by unanimous decision, and in doing so may have finished a long rivalry between the two with a 4–3 record head-to-head. The only other fighter he has fought 7 times was Yodsaenklai Fairtex.

Sam-a continued his great run of fighting in 2009 by starring in a classic rivalry with fan favorite, Pornsanae Sitmonchai. Within a 12-month period the two would go on to fight 5 times, with Sam-A winning 4 of those. His single loss would come in 2010 from a controversial knockdown called late in the fight. In this time, he emerged as a "Yodmuay" (super fighter) and became one of the few fighters in Thailand who were making 100,000 baht per fight. In 2010 he split wins over another rival, Rungruanglek Lukprabart. Towards the end of 2010, he would move up to 126 pounds and challenge top fighter Nong-O Sit Or at Lumpinee Stadium. Soon after, he would stay up in weight and again lose to a bigger fighter, Singtongnoi Por.Telakun. The size difference proved to be too much for Sam-A.

By 2008 he was one of the biggest stars in Muay Thai and was frequently headlining major shows. At the beginning of the year he beat Petchboonchu FA Group for the vacant bantamweight title of Thailand, and shortly after beat him again by a stoppage from an accumulation of kicks. Following a loss to Captainkane Narupai, Sam-A would stop top-tier fighters, Jenrop Sakhomsin, Penaik Sitnumnoi, and Rungruanglek Lukprabart all in a row. He closed the year out by capturing the Lumpinee championship with a win over Detnarong Wor. Sangprapai.

By the turn of the century Sam-A was fighting at both Lumpinee boxing stadium and Rajadamnern boxing stadium. He won his first stadium title in 2004 when he beat Petch T. Bangsean for the super flyweight championship of Lumpinee. Soon after he won the Thailand championship at the same weight.

Sam-A Gaiyanghadao (Thai: สามเอ ไก่ย่างห้าดาว; born October 13, 1983) is a Muay Thai fighter from Thailand currently signed to ONE Championship, where he is the reigning ONE Kickboxing Strawweight World Champion and ONE Muay Thai Strawweight World Champion. He is currently training and teaching in the prestigious Evolve MMA gym in Singapore. As of April 2020, Sam-A is ranked the #6 Strawweight in the world by Combat Press.